Phys.Rev. C 104, 015806 (2021)

M.Tessler, J.Zappala, S.Cristallo, L.Roberti, M.Paul, S.Halfon, T.Heftrich, W.Jiang, D.Kijel, A.Kreisel, M.Limongi, Z.-T.Lu, P.Muller, R.Purtschert, R.Reifarth, A.Shor, D.Veltum, D.Vescovi, M.Weigand, L.Weissman

Stellar s-process neutron capture cross sections on ^{78, 80, 84, 86}Kr determined via activation, atom trap trace analysis, and decay counting

NUCLEAR REACTIONS ^78,80,84,86Kr(n, γ)⁷⁹Kr/^79mKr/⁸⁰Kr/⁸¹Kr/^81mKr/⁸⁴Kr/⁸⁵Kr/^85mKr/⁸⁷Kr, kT=42.5 keV, quasi-Maxwellian; ^80,86Kr(γ, n)⁷⁹Kr/^85mKr, E=14.6, 17.6 MeV; measured Eγ, Iγ, average σ(E), ⁸¹Kr/⁸⁰Kr and ⁸⁵Kr/⁸⁴Kr isotopic ratios in (n, γ) reactions by activation method, Atom Trap Trace Analysis (ATTA) and decay counting at SARAF-LiLiT facility, Argonne National Laboratory and low-level counting (LLC) facility of the University of Bern; deduced Maxwellian-averaged cross sections (MACS) at kt=3-300 keV, and stellar reaction rates for s-process in 0.01-4 GK range for (n, γ) reactions. ¹⁹⁷Au(n, γ)¹⁹⁸Au, kT=42.5 keV; ¹⁹⁷Au(γ, n)¹⁹⁶Au, E=14.6, 17.6 MeV; measured Eγ, Iγ, used as monitor reactions. Comparison with previous experimental cross sections, and with data in JEFF-3.3 library. Discussed astrophysical implications, and impact on s-process calculations of abundances of krypton and neighboring nuclides.

RADIOACTIVITY ⁷⁹Kr(EC); ^85mKr(IT); ^85mKr, ⁸⁷Kr(β^-)[from ^78,84,86Kr(n, γ), kT=42.5 keV]; measured half-lives from γ-decay curves and compared with evaluated data.

doi: 10.1103/PhysRevC.104.015806